Just be careful if he does a fasting test and its ok and drops the diabetes thing that you stay keto or at least keep testing after meals if you relax away from it a bit. The problem is that you may be getting high results after eating that go back to normal over time.
You will have to be very careful from now on not to go back to carbs or stop testing no matter what he says after your test or you could end up with a nasty shock further down the line.
If you were 49 on your previous diet, you will be 49 and increasing if you go back to that diet no matter if your formally diagnosed next week or not.
the same applies to HBA1C though, if you have been Keto, its likely you will have dropped your HBA1C, maybe back to normal. All that means is that you would know its worked, you wouldn't get diagnosed but if 3 months later you go back to your old diet you will shoot right back upto 49 but with no follow ups at the Dr's planned.
What i would do if he does a fasting test and its ok, is request that you get another HBA1C in 3 months or 6 months time and see how you do sticking at Keto.